There is a continuing search for materials having desirable fragrance properties. Such materials are used either to replace costly natural materials or to provide new fragrances of perfumed types which have not heretofore been available. Especially desirable qualities for substances havng interesting fragrances such as sandalwood-type fragrances are stability and persistence, particularly in a wide variety of perfumed articles (e.g. soaps, detergents and powders) perfumed compositions and colognes, ease of manufacture and intensity of aroma.
Furthermore, according to Guenther [E. Guenther, "The Essential Oils," Vol. V. page 173, D. Van Nostrand Co., Inc., New York (1952)], East Indian sandalwood oil "has been perhaps one of the most precious perfumery materials from antiquity down to modern times, and its popularity has shown no signs of waning." This oil is widely used in perfumery, and would be even more widely used except for its limited supply and high cost.
As is well known, a need exists for synthetic substances which can be used as sandalwood substitutes or extenders. It would be most desirable to be able to synthetically provide the major odorant compounds of the natural sandalwood oil, i.e., alpha-santalol and beta-santalol, but no commercially feasible route to these chemicals is known at this time.
It would be even more desirable to provide a synthetic compound which would have many of the desirable odor qualities of a fine East Indian sandalwood oil, yet not have the potentially labile primary allylic alcohol group present in the natural santalols. A compound which would be more resistant to acidic or oxidative decomposition as well as being base stable could be even more versatile than sandalwood oil itself.
There is no obvious explanation why only slight chemical changes should have such a dramatic effect on odor intensity other than to invoke the general unreliability of odor structure relationships. Why the addition or removal of a methyl group, the removal of a double bond or the mere moving of a methyl group would essentially destroy more than 90% of the odor intensity rather than merely cause subtle odor differences comparable to the subtle chemical differences cannot be explained by any theoretical concepts in the known art.
U.S. Pat. No. 4,052,341, issued on Oct. 4, 1977 provides a sandalwood type aroma imparting material having one of the structures:
TABLE I ______________________________________ Name Structure ______________________________________ 3-Methyl-5-(2,2,3- trimethylcyclopent-3- en-1-yl)pentan-2-ol ##STR2## 3-Methyl-5-(2,2,3- trimethylcyclopentan-1- yl)pentan-2-ol ##STR3## 5-(2,2,3-Trimethyl- cyclopent-3-en-1-yl) pentan-2-ol ##STR4## 6-(2,2,3-Trimethyl- cyclopent-3-en-1-yl) hexan-3-ol ##STR5## 4-Methyl-6-(2,2,3- trimethylcyclopent-3- en-1-yl)hexan-3-ol ##STR6## 3-Ethyl-5-(2,2,3- trimethylcyclopent- 3-en-1-yl)pentan-2-ol ##STR7## 3-Methyl-5-(2,2,3- trimethylcyclopent-3- en-1-(R)-yl)pentan-2-ol ##STR8## 3-Methyl-5-(2,2,3- trimethylcyclopent- 3-en-1-(S)-yl)pentan-2-ol ##STR9## 3-Methyl-5-(2,2,3- trimethylcyclopent- 3-en-1-yl)pent-3-en-2-ol ##STR10## ______________________________________
These materials are produced according to the reaction schemes:
TABLE II __________________________________________________________________________ ##STR11## ##STR12## __________________________________________________________________________ (a) R.sub.1 = H, CH.sub.3, C.sub.2 H.sub.5R.sub.2 = H, CH.sub.3
East Germany Pat. No. 68,936 discloses for use in the sandalwood area a compound having the structure: ##STR13## Furthermore, Chemical Abstracts Volume 72, 125008b sets forth a genus for the East German 68,936 encompassing the following group of compounds: ##STR14## wherein R.dbd.CH.sub.2 OH, CHCH.sub.3 OH and R'.dbd.H,CH.sub.3 or C.sub.2 H.sub.5.
The compounds of our invention, defined according to the generic structure: ##STR15## wherein at least one of the lines ++++ is a carbon-carbon single bond and the other of the lines ++++ is either a carbon-carbon single bond or a carbon-carbon double bond, which imparts thereto woody, sandalwood aromas, have unobvious and unexpected properties insofar as their perfumery properties are concerned.
Chemical Abstracts 92: 93595g is an Abstract of Japanese Kokai (Published Patent Application) No. 79,125,645, assigned to the Takasago Perfumery Co., Ltd. and indicates the usefulness in perfumes of, interalia, the compound having the structure: ##STR16## and indicates that this compound is produced using the reduction of the corresponding unsaturated ketone having the structure: ##STR17## by means of hydrogenation over a copper chromite catalyst in isopropyl alcohol containing a small quantity of potassium hydroxide at 120.degree. C. The publication date of the subject Japanese Kokai 79,125,645 is Sept. 29, 1979 which is subsequent to the filing date of the parent application Ser. No. 932,677 filed on Aug. 10, 1978. In addition, the compounds of our invention have unexpected, unobvious and advantageous properties with respect to the lower methylene homologues of Japanese Kokai No. 79,125,645.